The owner of a ferry that sunk in Papua New Guinea has told an inquiry the number of passengers was much higher than usual when the Rabaul Shipping-operated ferry went down.

Captain Peter Sharp, the managing director and major shareholder of the operator of the Rabaul Queen that sank in February, told the inquiry examining the disaster there were 350 people onboard when it went down.

He said as far as he knew that was the most it had ever carried.

Captain Sharp said it usually carried around 300 passengers during peak periods.

He said the ferry had travelled the same route for more than a decade and the crew was reasonably trained.

The inquiry is trying to determine the exact number of victims and their identities.

Estimates of the death toll from different state agencies range from 100 to more than 200.